What is the recommended dosage of ibuprofen (nonsteroidal anti-inflammatory drug (NSAID)) based on body weight?

Ibuprofen Weight-Based Dosing

For children, use 10 mg/kg every 6-8 hours with a maximum daily dose of 30-40 mg/kg; for adults, use 400-800 mg every 6 hours with a maximum of 2400 mg per day. 1, 2

Pediatric Dosing (Children and Infants)

Standard Weight-Based Dosing

• Administer 5-10 mg/kg per dose every 6-8 hours 3, 4
• The most effective dose range is 7.5-10 mg/kg, with clinical trials demonstrating optimal efficacy at this level 4
• Maximum total daily dose: 30-40 mg/kg per day (when dosing 3-4 times daily) 3

Age-Specific Considerations

• Infants 3-6 months old: Safe for short-term use if body weight is above 5-6 kg, with special attention to hydration status 3
• Children weighing more than 40 kg: Dose as adults 5

Practical Dosing Example

• A 20 kg child would receive 200 mg per dose (10 mg/kg), administered every 6-8 hours, not exceeding 800 mg daily 3, 4

Adult Dosing

Standard Dosing by Indication

• Acute pain/fever: 400 mg every 4-6 hours as needed 2
• Moderate to severe pain (migraine, back pain): 400-800 mg every 6 hours 2
• Maximum daily dose: 2400 mg per day 2, 1

High-Dose Considerations

• Prescription doses up to 3200 mg/day may be used for cancer pain, but this exceeds standard OTC recommendations 1
• Anti-rheumatic doses can reach 2400 mg/day for chronic inflammatory conditions 6

Critical Safety Parameters

Mandatory Monitoring for Long-Term Use

• Blood pressure monitoring required 2
• BUN and creatinine levels 2
• Liver function tests 2
• Complete blood count 2
• Fecal occult blood testing 2

Immediate Discontinuation Criteria

• Stop immediately if: BUN or creatinine doubles, hypertension develops or worsens, liver function tests exceed normal limits, or gastrointestinal bleeding occurs 2, 1

High-Risk Populations Requiring Dose Modification

Patients Requiring Extreme Caution or Avoidance

• Age >60 years: Increased risk of all NSAID-related adverse effects 2
• Renal dysfunction, heart failure, cirrhosis: Avoid or use extreme caution 2
• History of peptic ulcer disease: 5% risk of recurrent bleeding within 6 months even with protective measures 2
• Concomitant anticoagulant use: 5-6 times increased GI bleeding risk 2

Absolute Contraindications

• Aspirin/NSAID-induced asthma 2
• Perioperative pain in coronary artery bypass graft surgery 2

Common Pitfalls to Avoid

Route of Administration in Infants

• Avoid rectal administration in young infants: Erratic absorption makes this route unreliable, particularly in infants under 6 months 3
• Prefer oral route for predictable absorption and dosing accuracy 3

Duration of Action Considerations

• Ibuprofen 400 mg provides at least 6 hours of analgesia, compared to 4-6 hours for 200 mg doses 7
• Peak temperature reduction occurs 3-4 hours after administration in children 4

Hydration Status

• Ensure adequate hydration before administering to infants 3-6 months old, as dehydration increases renal toxicity risk 3

Dosing Precision

• Always calculate pediatric doses based on actual body weight, not age alone 3, 4
• Use the lowest effective dose for the shortest duration to minimize adverse effects 2